The fact that Jacob so easily put people -even otherwise well-trained troops- at ease around him was just one of the things that made Hux suspicious.

Granted, he was suspicious of a lot of people for a lot of reasons, but being at ease with someone tended to mean that one would let things slip around that person that they wouldn't around others, and that was wholly unacceptable and not permissible as far as Hux was concerned. He knew, of course, that the Knights of Ren as a whole would learn what his Death Troopers were capable of, but they only needed to know what Jacob, Icarus, had learned via the training itself, nothing further.

"That's rather the point of not giving a warning in advance." He replied, one brow lifting a little, "Though I will say I'm surprised." Not impressed, though he was, a little, "This is the quickest one of these has been finished since the spectacular failure of the first."